raw: avoid two atomics in xmit

Avoid two atomic ops per raw_send_hdrinc() call

Avoid two atomic ops per raw6_send_hdrinc() call

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

2 files changed, 12 insertions, 8 deletions

diff --git a/net/ipv4/raw.c b/net/ipv4/raw.c
index 2c7a1639388a..66cc3befcd44 100644
--- a/net/ipv4/raw.c
+++ b/net/ipv4/raw.c
@@ -314,7 +314,7 @@ int raw_rcv(struct sock *sk, struct sk_buff *skb)
 }
 
 static int raw_send_hdrinc(struct sock *sk, void *from, size_t length,
-                        struct rtable *rt,
+                        struct rtable **rtp,
                         unsigned int flags)
 {
         struct inet_sock *inet = inet_sk(sk);
@@ -323,6 +323,7 @@ static int raw_send_hdrinc(struct sock *sk, void *from, size_t length,
         struct sk_buff *skb;
         unsigned int iphlen;
         int err;
+        struct rtable *rt = *rtp;
 
         if (length > rt->u.dst.dev->mtu) {
                 ip_local_error(sk, EMSGSIZE, rt->rt_dst, inet->inet_dport,
@@ -341,7 +342,8 @@ static int raw_send_hdrinc(struct sock *sk, void *from, size_t length,
 
         skb->priority = sk->sk_priority;
         skb->mark = sk->sk_mark;
-        skb_dst_set(skb, dst_clone(&rt->u.dst));
+        skb_dst_set(skb, &rt->u.dst);
+        *rtp = NULL;
 
         skb_reset_network_header(skb);
         iph = ip_hdr(skb);
@@ -576,7 +578,7 @@ back_from_confirm:
 
         if (inet->hdrincl)
                 err = raw_send_hdrinc(sk, msg->msg_iov, len,
-                                        rt, msg->msg_flags);
+                                        &rt, msg->msg_flags);
 
          else {
                 if (!ipc.addr)
diff --git a/net/ipv6/raw.c b/net/ipv6/raw.c
index 864eb8e03b1b..968b96490729 100644
--- a/net/ipv6/raw.c
+++ b/net/ipv6/raw.c
@@ -602,13 +602,14 @@ out:
 }
 
 static int rawv6_send_hdrinc(struct sock *sk, void *from, int length,
-                        struct flowi *fl, struct rt6_info *rt,
+                        struct flowi *fl, struct dst_entry **dstp,
                         unsigned int flags)
 {
         struct ipv6_pinfo *np = inet6_sk(sk);
         struct ipv6hdr *iph;
         struct sk_buff *skb;
         int err;
+        struct rt6_info *rt = (struct rt6_info *)*dstp;
 
         if (length > rt->u.dst.dev->mtu) {
                 ipv6_local_error(sk, EMSGSIZE, fl, rt->u.dst.dev->mtu);
@@ -626,7 +627,8 @@ static int rawv6_send_hdrinc(struct sock *sk, void *from, int length,
 
         skb->priority = sk->sk_priority;
         skb->mark = sk->sk_mark;
-        skb_dst_set(skb, dst_clone(&rt->u.dst));
+        skb_dst_set(skb, &rt->u.dst);
+        *dstp = NULL;
 
         skb_put(skb, length);
         skb_reset_network_header(skb);
@@ -886,9 +888,9 @@ static int rawv6_sendmsg(struct kiocb *iocb, struct sock *sk,
                 goto do_confirm;
 
 back_from_confirm:
-        if (inet->hdrincl) {
-                err = rawv6_send_hdrinc(sk, msg->msg_iov, len, &fl, (struct rt6_info*)dst, msg->msg_flags);
-        } else {
+        if (inet->hdrincl)
+                err = rawv6_send_hdrinc(sk, msg->msg_iov, len, &fl, &dst, msg->msg_flags);
+        else {
                 lock_sock(sk);
                 err = ip6_append_data(sk, ip_generic_getfrag, msg->msg_iov,
                         len, 0, hlimit, tclass, opt, &fl, (struct rt6_info*)dst,